Construction equipment

ABSTRACT

Construction equipment of which protection structure for an operator&#39;s cab when rolling over can be constituted to be favorable in visibility, transportability, and assembling and disassembling operability is provided. For this purpose, the construction equipment includes an upper revolving superstructure frame ( 4 ) rotatably loaded on a base carrier ( 3 ); and an operator&#39;s cab ( 7 ), a working machine ( 5 ) and a counterweight ( 6 ) which are provided on the upper revolving superstructure frame. Further, an operator&#39;s cab protection frame ( 10 A), which includes an operator&#39;s cab protection member ( 11 ), supporting members ( 12 A,  13 A) for supporting the operator&#39;s cab protection member and mounting members ( 19, 19 ) with which base end portions of the supporting members are mounted to a vehicle body, is mounted to the upper revolving superstructure frame, and is provided upright behind the operator&#39;s cab.

TECHNICAL FIELD

The present invention relates to construction equipment, and particularly relates to construction equipment having a protection structure for an operator's cab at a time of rolling over.

BACKGROUND ART

Various kinds of means for preventing or restraining deformation of an operator's cab to protect the operator when construction equipment turns over (refers to the state in which the construction equipment turns about 90 degrees) or rolls over (refers to the state in which the construction equipment turns about 180 degrees or more) are conventionally proposed in the construction equipment. A structure in which a shock absorber is attached to a side surface portion of the operator's cab provided at an upper part of a vehicle body capable of being self-propelled to relieve an impact load which acts on the operator's cab by the shock absorber when the construction equipment turns over is described on pages 2 to 3 and in FIG. 4 of Japanese Patent Application Laid-open No. 11-61885 that is a first example of such means. An operator's cab is loaded on one of the left and right sides of an upper revolving superstructure frame rotatably loaded on an upper part of a base carrier of the construction equipment, on pages 2 to 3 and in FIG. 1 of Japanese Patent Laid-open No. 2000-230255 which is a second example. Further, a structure, in which a support member is placed on a side surface of the upper revolving superstructure frame and by a side of the operator's cab and the support member supports the construction equipment with the base carrier in the state in which the operator's cab is not in contact with the ground when the construction equipment turns over, is described.

The first example and the second example have the structure easily applicable to ordinary construction equipment, but the consideration is not made for the case in which the construction equipment goes beyond turning over and rolls over.

A structure, in which the periphery of an operator's cab is surrounded by a cab guard constituted of a portal frame body to protect the operator's cab by the cab guard when the construction equipment rolls over, is described on pages 4 to 5 and FIG. 1 and FIG. 4 of Japanese Patent Application Laid-open No. 2001-173017 which is the third example. An example of the construction equipment having an operator's cab protection structure relating to the prior art will be explained based on FIG. 7 and FIG. 8. When the left and right are mentioned hereinafter, they mean the left and right facing to the front of the vehicle (see FIG. 1).

In FIG. 7 and FIG. 8, in a hydraulic shovel 80, an upper revolving superstructure frame 82 is rotatably loaded on a base carrier 81, and a boom 83 of a working machine is placed at a central portion in the left and right direction of a front part, and a counterweight 84 is placed at a rear part, and an operator's cab 85 is placed at a left side of the front part, on the upper revolving superstructure frame 82. A cab guard 90 is placed to surround an operator's cab 85.

However, in the structure of a hydraulic excavator 80 shown in FIG. 7 and FIG. 8, the following problems occur as a result that the cab guard 90 is placed to surround the operator's cab 85.

(1) In order to make it possible to prevent or restrain deformation of the operator's cab 85 by the cab guard 90 when the hydraulic excavator 80 rolls over, it is necessary to make the cab guard 90 have an extremely strong structure, and the number of components of the cab guard 90 is large. This leads to an increase in the entire weight of the vehicle due to an increase in the weight of the operator's cab 85, and there arises the problem that reduction in the driving performance of the vehicle is caused.

(2) Further, there arises the problem that visibility to the front, to above and to the rear from the operator's cab 85 is inhibited by a thick supporting column of the cab guard 90.

(3) When the cab guard 90 exceeds a regulation value of the maximum vehicle width at the time of transportation when the hydraulic excavator 80 is moved by being loaded on a transport vehicle, or when the cab guard 90 is attached in an operation site of the hydraulic shovel 80, it is necessary to detach or attach the cab guard 90. However, the cab guard 90 has a number of mounting portions to the upper revolving superstructure frame 82 and the mounting portion space inside the vehicle body is small, thus extremely complicating its detaching and attaching operations. As a result, transportability and assembling and dissembling operability of the hydraulic excavator 80 having the cab guard 90 are reduced.

SUMMARY OF THE INVENTION

The present invention is made in view of the above-described problems, and has its object to provide construction equipment of which protection structure for an operator's cab when the construction equipment rolls over can be constituted to be favorable in visibility, and favorable in transportability, and assembling and disassembling operability.

In order to attain the above-described object, the construction equipment according to the present invention is construction equipment comprising a base carrier; an upper revolving superstructure frame rotatably loaded on the base carrier; and an operator's cab, a working machine and a counterweight which are provided on the upper revolving superstructure frame, and an operator's cab protection frame, which includes an operator's cab protection member, supporting members for supporting the operator's cab protection member and mounting members with which mounting base end portions of the supporting members are mounted to a vehicle body, is mounted to the upper revolving superstructure frame, and is provided upright behind the operator's cab.

According to the above constitution, the following operational effects can be obtained.

(1) When the construction equipment rolls over 180 degrees, the construction equipment abuts to the ground with the working machine and the operator's cab protection member, and therefore deformation of the operator's cab located between the working machine and operator's cab protection member can be prevented or restrained. Accordingly, the operator space inside the operator's cab can be secured by the working machine and the operator's cab protection member.

(2) Since the operator's cab protection frame including the operator's cab protection member has a simple structure, and is only provided upright in the vertical direction behind the operator's cab, the operator's cab protection frame can be applied to compact to large construction equipment easily at low cost. Since the number of components of the operator's cab protection frame is small and the number of mounting locations is small, attaching and detaching operations are facilitated.

(3) For the same reason as item (2), the operator's cab protection member can be provided without increasing the outside dimension of the construction equipment, and therefore transportability of the construction equipment is not reduced.

(4) The operator's cab protection frame including the operator's cab protection member is only provided behind the operator's cab, and therefore the visibility to the front, to the sides, and to above from the operator's cab can be enhanced.

In the construction equipment, the operator's cab protection frame may be mounted to a vertical plate member of the upper revolving superstructure frame. According to this constitution, the operator's cab protection frame is mounted to the vertical plate member of the vehicle body frame (the upper revolving superstructure frame of the hydraulic shovel), and therefore the attaching and detaching operations are easily performed from above the construction equipment. As a result, assembling and disassembling operability and attachability and detachability of the operator's cab protection frame can be enhanced.

In the construction equipment, the operator's cab protection frame may be mounted to an upper portion of the counterweight. According to this constitution, the operator's cab protection member can be provided by using the counterweight as the mounting portion even when it is difficult to mount the operator's cab protection frame on the upper revolving superstructure frame because the area on the upper revolving superstructure frame is small as in the rearward small revolving type hydraulic excavator in which the revolving radius of the rear end portion is approximately within the vehicle width, for example. As a result, even in the case of the rearward small revolving type hydraulic excavator, the assembling and disassembling operability and transportability are not impaired. As a result, the strong operator's cab protection frame can be also provided in the compact construction equipment easily at low cost.

According to the above constitutions according to the present invention, the construction equipment, which is capable of realizing restraint on deformation of the operator's cab when the construction equipment rolls over at low production cost with favorable assembling and disassembling operability and favorable transportability and visibility, can be provided.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of construction equipment according to an embodiment of the present invention;

FIG. 2 is a perspective view of an essential part of construction equipment according to a first embodiment of the present invention;

FIG. 3 is a perspective view of an essential part of construction equipment according to a second embodiment of the present invention;

FIG. 4 is a perspective view of an essential part of construction equipment according to a third embodiment of the present invention;

FIG. 5 is a perspective view of an essential part of construction equipment according to a fourth embodiment of the present invention;

FIG. 6 is a perspective view of an essential part of construction equipment according to a fifth embodiment of the present invention;

FIG. 7 is a side view of a hydraulic excavator as an example of construction equipment described in the third example of the prior art; and

FIG. 8 is a partially broken perspective view of an essential part of the hydraulic excavator in FIG. 7.

DETAILED DESCRIPTION OF THE INVENTION

Preferred embodiments of construction equipment according to the present invention will be described in detail below with a hydraulic excavator as an example, with reference to FIG. 1 to FIG. 6.

Based on FIG. 1 and FIG. 2, a first embodiment will be explained. In FIG. 1, in a hydraulic excavator 1, an upper revolving superstructure frame 4 is rotatably provided on a base carrier 3. On the upper revolving superstructure frame 4, a working machine 5 is placed at a central portion in a left and right direction of a front part, a counterweight 6 is placed at a rear part, an operator's cab 7 is placed at either one side (the left side in this example) of the left or the right of the front part. Machine rooms 8 a and 8 b are placed between the counterweight 6 and the operator's cab 7. A portal frame 10A (an operator's cab protection frame 10A, the first embodiment) or a portal frame 10B (an operator's cab protection frame 10B, a second embodiment) are placed in close vicinity to a rear surface of the operator's cab 7.

In FIG. 2, the operator's cab 7 is loaded on the left side of the front part of the upper revolving superstructure frame 4 via vibration isolators 7 b. The portal frame 10A includes an operator's cab protection member 11 which is placed in close vicinity to an upper side 7 a of the rear surface of the operator's cab 7 and approximately in parallel to the upper side 7 a, and a left and a right supporting columns 12A and 13A (supporting members 12A and 13A) which are mounted to the left and the right of the operator's cab protection member 11 and provided upright in the vertical direction. A reinforcement member 14 is mounted in between intermediate portions in the vertical direction of the left and the right supporting columns 12A and 13A. The lower portions of the left and the right supporting columns 12A and 13A are fastened to a predetermined number of threaded holes 4 a which are provided in an upper surface of a mounting portion of the upper revolving superstructure frame 4 with a predetermined number of bolts 19 (mounting members 19).

According to a constitution of the first embodiment, the following operation and effects are obtained.

(1) When the hydraulic excavator 1 rolls over, the operator's cab protection member 11 of the portal frame 10A and the working machine 5 is in contact with the ground, whereby the hydraulic excavator 1 is supported by the portal frame 10A and the working machine 5, and therefore deformation of the operator's cab 7 which is located between the portal frame 10A and the working machine 5 is prevented or restrained. As a result, the operator space inside the operator's cab 7 is secured.

(2) At this time, the portal frame 10A is placed in close vicinity to the rear surface of the operator's cab 7 to place the operator's cab protection member 11. As a result, the strong operator's cab protection frame 10A can be placed easily in small to large construction equipment.

(3) The operator's cab protection frame 10A is placed in close vicinity to the rear surface of the operator's cab 7, and therefore the operator's cab protection frame 10A can be placed without increasing the outer dimension of the hydraulic excavator 1. As a result, transportability and assembling and disassembling operability of the hydraulic excavator 1 can be enhanced.

(4) The conventional cab guard does not exist at the front part and the upper part of the operator's cab 7, and visibility to the front, to the sides and to above can be enhanced. In addition, the portal frame 10A provided in close vicinity to the rear surface of the operator's cab 7 is located behind the rear surface wall of the operator's cab 7, and therefore the portal frame 10A does not inhibit visibility to the rear.

Based on FIG. 3, a second embodiment will be explained. A portal frame 10B includes the operator's cab protection member 11 placed in close vicinity to the upper side 7 a of the rear surface of the operator's cab 7, the left and the right supporting columns 12A and 13B (supporting members 12A and 13B) which are mounted to the left and the right of the operator's cab protection member 11 and are provided upright in the vertical direction, and a reinforcement member 14 mounted in between the intermediate portions in the vertical direction of the left and right supporting columns 12A and 13B. A mounting seat 4 c is placed on an outside surface of the vertical plate member 4 b at the side of the operator's cab 7 among a pair of left and right vertical plate members 4 b and 4 b which are provided at the upper revolving superstructure frame 4 and support a base end portion of the working machine 5 (see FIG. 1) to be swingable up and down. The supporting column 13B placed at an inner side of the vehicle body is fastened to a predetermined number of bolt holes 4 d of the mounting seat 4 c with a predetermined number of bolts 19 from the inner side of the vehicle body (namely, from the direction between a pair of left and right vertical plate members 4 b and 4 b).

According to the constitution of the second embodiment, the following operation and effects are obtained in addition to those of the first embodiment.

(1) The supporting column 13B at the inner side of the portal frame 10B is made shorter than the supporting column 12A at the outer side, and is mounted to the mounting seat 4 c located at a high position of the upper revolving superstructure frame 4, whereby the strength of the portal frame 10B can be made higher.

(2) It is made possible for an operator to have an access to the mounting portion of the supporting column 13B at the inner side to the upper revolving superstructure frame 4 from above the center of the upper revolving superstructure frame 4, namely, from above the hydraulic excavator 1. As a result, access is facilitated, and a large working space can be secured around the mounting portion, whereby the assembling and disassembling operability of the portal frame 13B can be further enhanced.

Based on FIG. 4, a third embodiment will be explained. A portal frame 10C (an operator's cab protection frame 10C) includes the operator's cab protection member 11 placed in close vicinity to the upper side 7 a of the rear surface of the operator's cab 7, left and right supporting columns 12B and 13C (supporting members 12B and 13C) which are mounted to the left and the right of the operator's cab protection member 11 and are provided upright in the vertical direction, and the reinforcement member 14 mounted in between the intermediate portions in the vertical direction of the left and the right supporting columns 12B and 13C. The portal frame 10C is placed to straddle the machine room 8 b adjacent to a rear side of the operator's cab 7. The left and the right supporting columns 12B and 13C of the portal frame 10C are respectively fastened to a predetermined numbers of threaded holes 4 f of a mounting seat 4 e which is placed at the outside surface of the upper revolving superstructure frame 4 and to a predetermined number of bolt holes 4 h of a mounting seat 4 g which is provided upright on the upper surface of the vertical plate member 4 b at the side of the operator's cab among a pair of left and right vertical plate members 4 b and 4 b, with a predetermined number of bolts 19.

According to the constitution of the third embodiment, the following operation and effects can be obtained in addition to those of the second embodiment. It is made possible to mount the portal frame 10C without having an influence on the machine room 8 b (see FIG. 1 and FIG. 4) adjacent to the rear side of the operator's cab 7, whereby the portal frame 10C can be additionally mounted to the existing construction equipment. As a result, the portal frame 10C can be easily mounted to the construction equipment of the basic specifications as an option. Further, the portal frame 10C can be easily attached and detached in accordance with the circumstances.

Based on FIG. 5, a fourth embodiment will be explained. The hydraulic excavator 2 is a rear small revolving type hydraulic excavator in which the turning radius of the rear portion is approximately within the vehicle width. A guard frame 20A (an operator's cab protection frame 20A) provided to project obliquely toward the upper side 7 a of the rear surface of the operator's cab 7 is mounted to a top surface of the counterweight 6 of the hydraulic excavator 2 with a predetermined number of bolts 19. The guard frame 20A includes the operator's cab protection member 11 which is placed to be in close vicinity to the upper side 7 a of the rear surface of the operator's cab 7 and approximately parallel to the upper side 7 a, a pair of arm-shaped members 21 and 22 (supporting members 21 and 22) at the left and right which are mounted to the left and the right portions of the operator's cab protection member 11 to face obliquely downward to the rear, and a flange member 23 which connects lower end portions of the left and the right arm-shaped members 21 and 22, and is mounted to the counterweight 6.

According to the constitution of the fourth embodiment, the following operation and effects are obtained.

(1) When the hydraulic excavator 2 rolls over, the hydraulic excavator 2 is supported by the operator's cab protection member 11 of the guide frame 20A and the working machine 5, and therefore deformation and damage of the operator's cab 7 which is located between the operator's cab protection member 11 and the working machine 5 are prevented or restrained, thus securing the operator space inside the operator's cab 7.

(2) At this time, the operator's cab protection member 11 can be placed in close vicinity to the upper side 7 a of the rear surface of the operator's cab 7 by placing the guard frame 20A at the counterweight 6, the strong operator's cab protection frame can be easily placed in small to large construction equipment.

(3) Since the guard frame 20A is placed on the counterweight 6, the operator's cab protection frame 20A can be provided without increasing the outer dimension of the hydraulic excavator 2. As a result, transportability and assembling and disassembling operability of the hydraulic excavator 2 can be enhanced.

(4) The conventional cab guard does not exist at the front part and the upper part of the operator's cab 7, and therefore visibility to the front, to the sides and to above can be enhanced.

(5) When the area on the upper revolving superstructure frame 4 is small as in the rear small revolving type hydraulic excavator 2, and thereby it is difficult to place the portal frame 10A (see FIG. 1 and FIG. 2) as shown in the first embodiment on the upper revolving superstructure frame 4, the operator's cab protection frame (guard frame 20A) can be placed with the counterweight 6 as the base bottom. Accordingly, transportability and assembling and disassembling operability of the rear small revolving type hydraulic excavator 2 are not impaired. As a result, the operator's cab protection frame can be also easily provided in the compact construction equipment.

(6) Since the guard frame 20A is mounted to the counterweight 6, this mounting does not have an influence on the placement of the other devices. As a result, the guard frame 20A can be mounted to the construction equipment of the basic specifications as an option. The guard frame 20A can be easily attached and detached in accordance with the circumstances.

Based on FIG. 6, a fifth embodiment will be explained. A guard frame 20B (an operator's cab protection frame 20B) which is provided to project toward the upper side 7 a of the rear surface of the operator's cab 7 is mounted to the upper surface of the counterweight 6 of the hydraulic excavator 2 with a predetermined number of bolts 19. The guard frame 20B includes the operator's cab protection member 11 which is placed in close vicinity to the upper side 7 a and approximately parallel to the upper side 7 a, a pair of left and right arm-shaped members 21 and 22 which are mounted to the left and the right of the operator's cab protection member 11 toward the rear, and a portal frame 24, to which rear end portions of a pair of left and right arm-shaped members 21 and 22 are mounted to support the members 11, 21 and 22. In the portal frame 24, upper ends of the left and the right support columns 25 and 26 (support members 25 and 26) are connected with a beam 27, and flanges 25 a and 26 a are provided at respective lower end portions of the supporting columns 25 and 26.

According to the constitution of the fifth embodiment, the guard frame 20B is also mountable when the thickness in the longitudinal direction of the central portion of the counterweight 6 is small. Otherwise, the operation and the effects are the same as those in the fourth embodiment.

In each of the constitutions shown in the first to the fifth embodiments, the operator's cab 7 and the operator's cab protection member 11 do not overlap each other in the side view, but the present invention is not limited to this, and for example, parts such as upper parts of them may overlap each other. Further, for example, the operator's cab 7 and the operator's cab protection member 11 may be connected via a vibration isolator (not shown) having an elastic member such as rubber. This makes it possible to easily prevent the excessive swing of the operator's cab 7 which is loaded on the upper revolving superstructure frame 4 via the vibration isolators 7 b (see FIG. 2) with the above-described vibration isolators between the operator's cab 7 and the operator's cab protection member 11.

The portal frames 10A, 10B and 10C each have the reinforcement member 14, but the present invention is not limited to this. For example, presence and absence and the shape of the reinforcement member may be optionally selected in consideration of the machine to which the portal frame is applied, necessary strength, outer appearance and the like. Further, as the members which are used for the portal frames 10A, 10 b and 10C, and the guard frames 20A and 20B, a square bar, a round bar, a pipe member and the like can be used, and the members may be constituted of not only the welded structure but also a pipe member for which bent work is performed, the combination of these and the like.

As explained thus far, according to the present invention, the operator's cab protection frame (the portal frames 10A, 10B and 10 c, and the guard frames 20A, 20B and the like in the embodiments) having the operator's cab protection member provided in close vicinity to the upper part of the rear surface of the operator's cab of the construction equipment is mounted on the upper revolving superstructure frame or on the counterweight. When the construction equipment rolls over, the operator's cab is supported by the operator's cab protection frame, and the working machine which is provided at the front part of the vehicle body frame (the upper revolving superstructure frame in the embodiments). As a result, the number of components of the operator's cab protection frame is reduced, and the number of mounting locations is small, thus making it possible to enhance operability at the time of assembly and disassembly.

Since the operator's cab protection frame is provided only behind the operator's cab, visibility to the front and to above from the operator's cab can be enhanced. The mounting portion at the inner side of the vehicle body for the operator's cab protection frame is mounted to the working machine supporting frame of the vehicle body frame, whereby assembling and disassembling operability of the operator's cab protection frame can be further enhanced. Further, since the operator's cab protection frame can be provided within the turning range of the upper revolving superstructure when the operator's cab protection frame is applied to a hydraulic excavator, the turning range and the maximum vehicle width are not increased, and transportability of the hydraulic excavator is not impaired.

The present invention is applicable to the construction equipment in which the working machine and the operator's cab are provided on the vehicle body frame, and the present invention can be applied to, for example, a crane truck, forestry equipment (timber transporting vehicle and the like) and the like other than the hydraulic excavators. 

1. Construction equipment comprising a base carrier; an upper revolving superstructure frame rotatably loaded on said base carrier; and an operator's cab, a working machine and a counterweight which are provided on said upper revolving superstructure frame, wherein an operator's cab protection frame, which includes an operator cab protection member, supporting members for supporting said operator's cab protection member, and mounting members with which mounting base end portions of said supporting members are mounted to a vehicle body, is mounted to said upper revolving superstructure frame, and is provided upright behind said operator's cab.
 2. The construction equipment according to claim 1, wherein said operator's cab protection frame is mounted to a vertical plate member of said upper revolving superstructure frame.
 3. The construction equipment according to claim 1, wherein said operator's cab protection frame is mounted to an upper portion of said counterweight. 